[users@httpd] Incompatibility Apache reverse proxy and Internet Explorer?

[Spil Oss <sp...@googlemail.com>]

Hi all,

Spuriously we get "Server not found or DNS Error" in Internet Explorer
for a site that is reversed proxied with Apache.
Please find a txt export of the pcap dump attached.

What seems to happen is that the reverse proxy returns FIN, ACK on the
3 connections from IE and subsequently a RST. This then triggers IE
into displaying the "Server not found or DNS Error" message.
Disabling "Show friendly HTTP error messages" seems to help, but we
can't force "the whole world" to change that setting in their Internet
Explorer browser (if that were possible for users in a business
environment anyway)

The setup:
Internet Explorer ->
Reverse Proxy DMZ1 ->
Reverse Proxy DMZ2 ->
Application Server
v.v.

The reverse proxies have simple proxy rules like
ProxyPass /b2b_portal/ http://dmz2web.domain.com:8080/b2b_portal/
<Location /b2b_portal/>
   ProxyPassReverse /b2b_portal/
</Location>

and on dmz2web
ProxyPass /b2b_portal/ http://app1.domain.com:80/b2b_portal/
<Location /b2b_portal/>
   ProxyPassReverse /b2b_portal/
</Location>

The DMZ1 proxy is connected via ssl, the other connections are plain http.

Anyone experience this before and/or can explain this behaviour of the
apache reverse proxy? (2.2.3-ssl running on Windows 2003)

PS. We used IIS as reverse proxy before and that was fine.....
PS. No such behaviour using Firefox 1.5/2.0

Help is very much appreciated!

Kind regards,

Spil.

D:\Apache2.2>bin\httpd.exe -V
Server version: Apache/2.2.3
Server built: Aug 10 2006 17:29:16
Server's Module Magic Number: 20051115:3
Server loaded: APR 1.2.7, APR-Util 1.2.7
Compiled using: APR 1.2.7, APR-Util 1.2.7
Architecture: 32-bit
Server MPM: WinNT
threaded: yes (fixed thread count)
forked: no
Server compiled with....
-D APACHE_MPM_DIR="server/mpm/winnt"
-D APR_HAS_SENDFILE
-D APR_HAS_MMAP
-D APR_HAS_OTHER_CHILD
-D AP_HAVE_RELIABLE_PIPED_LOGS
-D DYNAMIC_MODULE_LIMIT=128
-D HTTPD_ROOT="/apache"
-D SUEXEC_BIN="/apache/bin/suexec"
-D DEFAULT_SCOREBOARD="logs/apache_runtime_status"
-D DEFAULT_ERRORLOG="logs/error.log"
-D AP_TYPES_CONFIG_FILE="conf/mime.types"
-D SERVER_CONFIG_FILE="conf/httpd.conf"

D:\Apache2.2>bin\httpd.exe -M
Loaded Modules:
core_module (static)
win32_module (static)
mpm_winnt_module (static)
http_module (static)
so_module (static)
actions_module (shared)
alias_module (shared)
asis_module (shared)
auth_basic_module (shared)
authn_default_module (shared)
authn_file_module (shared)
authz_default_module (shared)
authz_groupfile_module (shared)
authz_host_module (shared)
authz_user_module (shared)
autoindex_module (shared)
cgi_module (shared)
dir_module (shared)
env_module (shared)
imagemap_module (shared)
include_module (shared)
isapi_module (shared)
log_config_module (shared)
mime_module (shared)
proxy_module (shared)
proxy_connect_module (shared)
proxy_http_module (shared)
negotiation_module (shared)
rewrite_module (shared)
setenvif_module (shared)
userdir_module (shared)
ssl_module (shared)
Syntax OK